72487471991 has 32 divisors (see below), whose sum is σ = 83187371520. Its totient is φ = 62521430400.

The previous prime is 72487471981. The next prime is 72487472017. The reversal of 72487471991 is 19917478427.

It is not a de Polignac number, because 72487471991 - 2³⁴ = 55307602807 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72487471991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72487471981) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16393961 + ... + 16398381.

It is an arithmetic number, because the mean of its divisors is an integer number (2599605360).

Almost surely, 2^72487471991 is an apocalyptic number.

72487471991 is a deficient number, since it is larger than the sum of its proper divisors (10699899529).

72487471991 is a wasteful number, since it uses less digits than its factorization.

72487471991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4967.

The product of its digits is 7112448, while the sum is 59.

The spelling of 72487471991 in words is "seventy-two billion, four hundred eighty-seven million, four hundred seventy-one thousand, nine hundred ninety-one".